r - 在 map 上独立移动 2 个图例 ggplot2

Question

我想在 map 上独立移动两个图例以保存保存并使演示文稿更好。

这是数据:

##              INST..SUB.TYPE.DESCRIPTION Enrollment      lat       lng
## 1                        CHARTER SCHOOL        274 42.66439 -73.76993
## 2                 PUBLIC SCHOOL CENTRAL        525 42.62502 -74.13756
## 3     PUBLIC SCHOOL CENTRAL HIGH SCHOOL         NA 40.67473 -73.69987
## 4                    PUBLIC SCHOOL CITY        328 42.68278 -73.80083
## 5            PUBLIC SCHOOL CITY CENTRAL        288 42.15746 -78.74158
## 6                  PUBLIC SCHOOL COMMON         NA 43.73225 -74.73682
## 7     PUBLIC SCHOOL INDEPENDENT CENTRAL        284 42.60522 -73.87008
## 8  PUBLIC SCHOOL INDEPENDENT UNION FREE        337 42.74593 -73.69018
## 9             PUBLIC SCHOOL SPECIAL ACT         75 42.14680 -78.98159
## 10             PUBLIC SCHOOL UNION FREE        256 42.68424 -73.73292

我在这篇文章中看到，您可以独立移动两个图例，但是当我尝试时，图例不会移动到我想要的位置(左上角，如 e1 情节，以及右中间，如 e2 情节)。

https://stackoverflow.com/a/13327793/1000343

最终所需的输出将与另一个网格图合并，因此我需要能够以某种方式将其分配为 grob。我想了解如何实际移动传说，因为另一篇文章为他们工作，它没有解释发生了什么。

这是我正在尝试的代码:

library(ggplot2); library(maps); library(grid); library(gridExtra); library(gtable)
ny <- subset(map_data("county"), region %in% c("new york"))
ny$region <- ny$subregion

p3 <- ggplot(dat2, aes(x=lng, y=lat)) + 
    geom_polygon(data=ny, aes(x=long, y=lat, group = group)) 

(e1 <- p3 + geom_point(aes(colour=INST..SUB.TYPE.DESCRIPTION, 
    size = Enrollment), alpha = .3) +
    geom_point() + 
    theme(legend.position = c( .2, .81),
        legend.key = element_blank(),
        legend.background = element_blank())  +
    guides(size=FALSE, colour = guide_legend(title=NULL, 
        override.aes = list(alpha = 1, size=5))))


leg1 <- gtable_filter(ggplot_gtable(ggplot_build(e1)), "guide-box") 



(e2 <- p3 + geom_point(aes(colour=INST..SUB.TYPE.DESCRIPTION, 
    size = Enrollment), alpha = .3) +
    geom_point() + 
    theme(legend.position = c( .88, .5),
        legend.key = element_blank(),
        legend.background = element_blank())  +
    guides(colour=FALSE))

leg2 <- gtable_filter(ggplot_gtable(ggplot_build(e2)), "guide-box") 

(e3 <- p3 + geom_point(aes(colour=INST..SUB.TYPE.DESCRIPTION, 
    size = Enrollment), alpha = .3) +
    geom_point() + 
    guides(colour=FALSE, size=FALSE))



plotNew <- arrangeGrob(leg1, e3, 
         heights = unit.c(leg1$height, unit(1, "npc") - leg1$height), ncol = 1)

plotNew <- arrangeGrob(plotNew, leg2,
          widths = unit.c(unit(1, "npc") - leg2$width, leg2$width), nrow = 1)

grid.newpage()
plot1 <- grid.draw(plotNew)


plot2 <- ggplot(mtcars, aes(mpg, hp)) + geom_point()
grid.arrange(plot1, plot2)

##我也绑了:

e3 + 
    annotation_custom(grob = leg2, xmin = -74, xmax = -72.5, ymin = 41, ymax = 42.5) +
    annotation_custom(grob = leg1, xmin = -80, xmax = -76, ymin = 43.7, ymax = 45)

## dput 数据:

dat2 <- 
structure(list(INST..SUB.TYPE.DESCRIPTION = c("CHARTER SCHOOL", 
"PUBLIC SCHOOL CENTRAL", "PUBLIC SCHOOL CENTRAL HIGH SCHOOL", 
"PUBLIC SCHOOL CITY", "PUBLIC SCHOOL CITY CENTRAL", "PUBLIC SCHOOL COMMON", 
"PUBLIC SCHOOL INDEPENDENT CENTRAL", "PUBLIC SCHOOL INDEPENDENT UNION FREE", 
"PUBLIC SCHOOL SPECIAL ACT", "PUBLIC SCHOOL UNION FREE"), Enrollment = c(274, 
525, NA, 328, 288, NA, 284, 337, 75, 256), lat = c(42.6643890904276, 
42.6250153712452, 40.6747307730359, 42.6827826714356, 42.1574638634531, 
43.732253, 42.60522, 42.7459287878497, 42.146804, 42.6842408825698
), lng = c(-73.769926191186, -74.1375573966339, -73.6998654715486, 
-73.800826733851, -78.7415828275227, -74.73682, -73.87008, -73.6901801893874, 
-78.981588, -73.7329216476674)), .Names = c("INST..SUB.TYPE.DESCRIPTION", 
"Enrollment", "lat", "lng"), row.names = c(NA, -10L), class = "data.frame")

所需输出:

Answer 1

顺便说一句，可以使用多个 annotation_custom :

library(ggplot2); library(maps); library(grid); library(gridExtra); library(gtable)
    ny <- subset(map_data("county"), region %in% c("new york"))
    ny$region <- ny$subregion

    p3 <- ggplot(dat2, aes(x = lng, y = lat)) + 
        geom_polygon(data=ny, aes(x = long, y = lat, group = group)) 

    # Get the colour legend
    (e1 <- p3 + geom_point(aes(colour = INST..SUB.TYPE.DESCRIPTION, 
        size = Enrollment), alpha = .3) +
        geom_point() + theme_gray(9) +
        guides(size = FALSE, colour = guide_legend(title = NULL, 
            override.aes = list(alpha = 1, size = 3))) +
        theme(legend.key.size = unit(.35, "cm"),
            legend.key = element_blank(),
            legend.background = element_blank()))

    leg1 <- gtable_filter(ggplot_gtable(ggplot_build(e1)), "guide-box") 

    # Get the size legend
    (e2 <- p3 + geom_point(aes(colour=INST..SUB.TYPE.DESCRIPTION, 
        size = Enrollment), alpha = .3) +
        geom_point() + theme_gray(9) +
        guides(colour = FALSE) +
        theme(legend.key = element_blank(),
            legend.background = element_blank()))

    leg2 <- gtable_filter(ggplot_gtable(ggplot_build(e2)), "guide-box") 

    # Get first base plot - the map
    (e3 <- p3 + geom_point(aes(colour = INST..SUB.TYPE.DESCRIPTION, 
        size = Enrollment), alpha = .3) +
        geom_point() + 
        guides(colour = FALSE, size = FALSE))


leg2Grob <- grobTree(leg2)
leg3Grob <- grobTree(leg2)
leg4Grob <- grobTree(leg2)
leg5Grob <- grobTree(leg2)
leg1Grob <- grobTree(leg1)

p = e3 +
  annotation_custom(leg2Grob, xmin=-73.5, xmax=Inf, ymin=41, ymax=43) +
  annotation_custom(leg1Grob, xmin=-Inf, xmax=-76.5, ymin=43.5, ymax=Inf) +
  annotation_custom(leg3Grob, xmin = -Inf, xmax = -79, ymin = -Inf, ymax =  41.5) +
  annotation_custom(leg4Grob, xmin = -78, xmax = -76, ymin = 40.5, ymax = 42) +
  annotation_custom(leg5Grob, xmin=-73.5, xmax=-72, ymin=43.5, ymax=Inf)
p